Systems for using sunlight to illuminate the interiors of buildings have been proposed for centuries. Such systems usually involve a receiver located on the roof of the building, a transmission channel within the structure itself, and a distributing element located in the interior of the building from which the light is dispersed. Such systems have usually been neither satisfactory nor commercially successful because of the awkwardness of the designs, the difficulty of construction and maintenance, and the inefficiencies of the receiving, transmitting, and distributing arrangements.
In addition, previous lighting systems utilizing sunlight have focused primarily on transmitting sunlight or a combination of sunlight and air into the interior of a structure. Only a few have provided alternative (artificial) light sources for use should the sunlight become insufficient for lighting purposes, or have provided automatic control; and the few systems which are known appear to be rudimentary in nature and incapable of practical usage to satisfy modern illumination requirements.
Also, few systems have utilized solar light collectors which automatically track the path of the sun, thereby optimizing the transfer of solar light into the structure. Those systems which have used such tracking devices have not provided alternative artificial sources for lighting the structure. Conversely, those system which have provided artificial sources of light have not used the tracking devices which are necessary to provide useful levels of solar illumination within a modern building.
Accordingly, a principal object of this invention is to reduce lighting costs by a simplified and effective system for transmitting sunlight from the exterior to the interior of a building and for automatically generating artificial light when the sunlight becomes unsatisfactory for illumination purposes.
It is an additional object of this invention to optimize transfer of sunlight and to provide for maximum control over its use in lighting the interior of the building.
It is another object of this invention to produce a lighting system, as described above, which utilizes conventional fluorescent lighting fixtures for distributing the solar light into the building interior.